Someone Threw a Homemade Explosive Through the Front Door of a Crowded Cheesecake Factory

Authorities are searching for a man who they say threw a homemade explosive into a crowded Cheesecake Factory in Pasadena, California, on Thursday night — a jarring incident and possible prank that did not result in injuries.

Shortly after 6 p.m., the man opened the restaurant’s front door and threw the device inside, where it landed under an empty table, police say. The suspect then fled as the device exploded.

No one was injured in the incident, but the scene quickly devolved.

“People were jumping over one another, fighting to get over bar stools. People were tripping, falling,” one witness told NBC Los Angeles, adding, “Stuff [was] going everywhere. It was very chaotic.”

Police evacuated the scene, and a bomb squad removed the device. While its exact nature hasn’t been released, authorities described the explosive as a “homemade pyrotechnic device” that was seemingly designed to create a loud noise and not “injure or maim,” police told NBC L.A.

It reportedly contained gunpowder, and Pasadena’s mayor told the Orange County Register it was more like a firecracker than a bomb.

Pasadena police told NBC L.A. on Friday that the incident appeared to be “a really bad prank.”

• Want to keep up with the latest crime coverage? Click here to get breaking crime news, ongoing trial coverage and details of intriguing unsolved cases in the True Crime Newsletter.

In a news conference, Pasadena Lt. Mark Goodman explained the device wasn’t a pipe bomb or a Molotov cocktail, and that it contained no projectiles or shrapnel.

Goodman told the Pasadena Star News that the man’s motive remains unclear. “It could be a dissatisfied customer, a disgruntled employee,” he said.

Pasadena police confirm to PEOPLE that they have notified the FBI and the Bureau of Alcohol, Tobacco and Firearms as detectives continue to gather information. The Cheesecake Factory confirmed the incident in a statement and said the Pasadena location would reopen Friday.

“Thankfully, none of our guests or staff was injured,” said Alethea Rowe, a company spokeswoman. “Law enforcement is actively investigating the incident.”

Anyone with information is asked to call Pasadena police at 626-744-4241 or L.A. Regional Crime Stoppers at 800-222-8477.